Constitution (Japanese: 体格Build), abbreviated as Con (Bld in Thracia 776, Cn in Radiant Dawn) is a statistic applied to units that represents that unit's physical size. Its original function was to alleviate the effects of the weight of the unit's currently-equipped weapon on that unit's attack speed in battle - prior to the statistic's introduction in Thracia 776, units' attack speed bore the full brunt of a weapon's weight, often crippling users of heavy weapon types such as axes. Constitution also affects whether or not units can rescue each other: a unit with a higher constitution can rescue one with lower, but not vice versa.

The Constitution stat lost many of its functions in Path of Radiance: in the attack speed calculation, it was replaced by Strength; the rescuing calculation instead used the new weight stat; and Aid was removed entirely. It, however, retained some niche usage in the calculations for the Colossus and Shove skills, in Path of Radiance and Radiant Dawn respectively.

Constitution was removed entirely in Shadow Dragon, and has not appeared since.

Other

Stealing

In Thracia 776, constitution affects the ability to steal. If a thief's constitution is greater than the weight of a weapon held, but not equipped, by an enemy, the thief can steal that weapon (assuming that the thief is faster than the target).